--- id: CVE-2026-63823 title: |- In the Linux kernel, the following vulnerability has been resolved: keys: Pin request_key_auth payload in instantiate paths A: request_key() B: KEYCTL_INSTANTIATE_IOV ================ ========================= create auth … summary: |- In the Linux kernel, the following vulnerability has been resolved: keys: Pin request_key_auth payload in instantiate paths A: request_key() B: KEYCTL_INSTANTIATE_IOV ================ ========================= create auth … severity: high cvss: 7.8 cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H' published: '2026-07-19' updated: '2026-08-17' source: NVD sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-63823' references: - url: 'https://git.kernel.org/stable/c/35ab4db86774d82389e4b9559e26ab7f68d8e395' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/4982bfabce6b33b3c9eddb4fb900fe5568b7cf91' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/708709c65a1832a99b0eef8ae46e343ddaca3d06' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/7216ce8cb12fee44e309503955bb83806b106129' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/83c0a1cb296d955d5f4d1f0bd8a769ba8ed8c29f' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/d8274181b0f28d450b42489723a5ba81042158d7' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/f9b68632ac93cc742f2e411021c4dbfe452ea0c2' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: 'https://git.kernel.org/stable/c/fd15b457a86939c38aa12116adabd8ff686c5e51' label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 - url: >- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-63823.json - url: 'https://access.redhat.com/security/cve/CVE-2026-63823' - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2502218' - url: 'https://www.cve.org/CVERecord?id=CVE-2026-63823' - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-63823' - url: >- https://lore.kernel.org/linux-cve-announce/2026071906-CVE-2026-63823-4e1e@gregkh/T - url: 'https://access.redhat.com/errata/RHSA-2026:70498' - url: 'https://access.redhat.com/errata/RHSA-2026:70459' - url: 'https://access.redhat.com/errata/RHSA-2026:70402' - url: 'https://access.redhat.com/errata/RHSA-2026:70403' tags: - nvd - csaf - vex - red-hat epss: 0.00124 epssPercentile: 0.01819 ingestedAt: '2026-08-17T05:47:49.844Z' vendor: Red Hat product: Red Hat Enterprise Linux BaseOS (v. 10) affected: - enterprise_linux 6 - enterprise_linux 7 - enterprise_linux 9 - enterprise_linux_appstream_v_10 - enterprise_linux_appstream_v_9 - enterprise_linux_baseos_v_10 - enterprise_linux_baseos_v_8 - enterprise_linux_baseos_v_9 - enterprise_linux_codeready_linux_builder_v_10 - enterprise_linux_crb_v_8 - enterprise_linux_codeready_linux_builder_v_9 - enterprise_linux_real_time_for_nfv_v_10 - enterprise_linux_nfv_v_8 - enterprise_linux_real_time_for_nfv_v_9 - enterprise_linux_real_time_v_10 - enterprise_linux_rt_v_8 - enterprise_linux_real_time_v_9 patched: - enterprise_linux_appstream_v_10 - enterprise_linux_appstream_v_9 - enterprise_linux_baseos_v_10 - enterprise_linux_baseos_v_8 - enterprise_linux_baseos_v_9 - enterprise_linux_codeready_linux_builder_v_10 - enterprise_linux_crb_v_8 - enterprise_linux_codeready_linux_builder_v_9 - enterprise_linux_real_time_for_nfv_v_10 - enterprise_linux_nfv_v_8 - enterprise_linux_real_time_for_nfv_v_9 - enterprise_linux_real_time_v_10 - enterprise_linux_rt_v_8 - enterprise_linux_real_time_v_9 cwe: - CWE-825 scores: nvd: 7.8 vendor: 7 --- ## Overview In the Linux kernel, the following vulnerability has been resolved: keys: Pin request_key_auth payload in instantiate paths A: request_key() B: KEYCTL_INSTANTIATE_IOV ================ ========================= create auth key store rka in auth key wait for helper get auth key load rka from auth key copy user payload sleep on #PF helper completed detach and free rka destroy auth key wake up use rka->target_key **USE-AFTER-FREE** Give request_key_auth payloads a refcount. Take a payload reference while authkey->sem stabilizes the payload and revocation state. Hold that reference across the instantiate and reject paths. Drop the auth key owning reference from revoke and destroy. [jarkko: Replaced the first two paragraphs of text with an actual concurrency scenario.] ## Remediation Refer to the linked advisories for vendor-supplied fixes and affected version ranges. ## Vendor advisories - **RHSA-2026:70498** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10), Red Hat Enterprise Linux Real Time for NFV (v. 10), Red Hat Enterprise Linux Real Time (v. 10) · released 2026-09-23 · [advisory](https://access.redhat.com/errata/RHSA-2026:70498) - **RHSA-2026:70459** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9), Red Hat Enterprise Linux Real Time for NFV (v. 9), Red Hat Enterprise Linux Real Time (v. 9) · released 2026-09-23 · [advisory](https://access.redhat.com/errata/RHSA-2026:70459) - **RHSA-2026:70402** · Red Hat · fixed in: Red Hat Enterprise Linux BaseOS (v. 8), Red Hat Enterprise Linux CRB (v. 8) · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:70402) - **RHSA-2026:70403** · Red Hat · fixed in: Red Hat Enterprise Linux NFV (v. 8), Red Hat Enterprise Linux RT (v. 8) · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:70403) - **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 9 · updated 2026-09-24 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-63823.json)